In this U19 application we propose to build upon our expertise in nonhuman primate stem cell transplantation (pigtail macaques), and carefully evaluate the effects of pretransplant conditioning regimens on the HIV reservoir. Our private sector partner will develop ZFNs capable of modifying the macaque CCR5 locus, and optimize methods for their delivery to CD34[+] stem cells. Combining these efforts, we will then perform autologous transplantation in macaques using the CCR5-modfied stem cells. In this way, we hope to recapitulate the well-known Berlin experiment, but using autologous cells such that this approach could be applied to the vast majority of HIV-infected individuals who do not have matched CCR5A32 donors. At the same time, we will develop SHIV-specific homing endonucleases that can directly modify proviral sequences within infected cells (rendering the provirus nonfunctional), and optimize methods for delivery of these HEs to CD4+ T cells and to CD34+ stem cells. We will then test the ability of these HEs to purge provirus from infected cells, using PBMC and stem cells obtained from the macaques in our transplant studies. This is a complex and highly interactive program bringing together experts in multiple fields. Thus, a strong administrative structure is critical to the successful performance of this work. The aims of the core are: SA1. Ensure that the U19 functions efficiently using effective administrative, fiscal, and scientific review procedures. SA2. Ensure that the U19 investigators communicate effectively with each other, with the broader scientific and clinical communities, with other collaborators, and with the program sponsor, NIH. SAS. Ensure that investigators in the U19 adhere to the highest ethical standards in conducting their research. The Administrative Core will coordinate the administrative, fiscal and organizational aspects of our U19 program, will facilitate scientific communication, and will provide fixed support services to each of the projects and cores. Our integrated research program includes leading scientists based at the FHCRC, the UW, Seattle Children's, City of Hope, and Sangamo Biosciences. Administrative staff members in the Core will provide a bridge between these institutions. All are experienced in coordination of the administrative complexities that a combined program creates.